Table of Contents
Introduction
In the digital world we live in, it’s important to learn how to be safe amidst all the online threats around you, and also learn how to check if your computer has a virus, and the first thing to do to keep yourself safe is to know and recognize the early warning signs of an infection before it causes you any serious harm.
Computer viruses are simply malicious software containing malicious code written by a specific programming language to disrupt, damage, or gain unauthorized access to your system. There are a wide variety of PC viruses, each one has a specific purpose to achieve.
PC viruses can slow down your PC by taking advantage of your PC ressources like the CPU and GPU to do unauthorized activities like mining cryptocurrencies, especially the most famous and expensive one in the market, Bitcoin. They can also corrupt your files, steal your data and even lock your important data and ask for a ransom.
Think of your private photos, videos, documents, passwords, credit card informations, important emails and so on. How would you feel if they are leaked online and you can’t do anything about it?
Keep in your mind: it’s better to be safe than sorry!
In this article, we’ll walk you through the most common signs a computer virus can show determine whether your PC really has a virus, you will learn how to detect and erase the existence of any virus you can think of using Windows’ built-in tools and trusted antivirus software. We will also show you how to protect yourself and your family while browsing the internet.
What Are PC Virus Types?
Common PC viruses known as malwares include Keyloggers, Adware, Spyware, Ransomware, Trojans, Worms and so on!
Keyloggers
Keyloggers are type of malware that records everything you type in your keyboard including passwords you type to enter a certain website or private messages with your friends and family. It’s a pretty simple malware to understand, just like the name suggests, a keylogger “logs” the keys you press. Even if it’s an easy malware to remember, it’s a serious threat to your privacy and security.
Adware
Adware is also a type of malware used to displays unwanted ads or pop-ups on your machine and the developer of this malicious software usually earn money through ads. Adware can slow down your machine as it takes advantage of your PC ressources and runs in the background.
Spyware
Spyware is a computer virus used to secretly monitor your computer activity by tracking your browsing searches, act like a keylogger and thus logging your keystrokes, capturing screenshots from your PC, and even accessing your webcam or microphone in some rare and extreme virus cases that are developed smartly by experienced cyberattackers.
Ransomware
Ransomware is a serious malware that use strong encryption algorithms like “AES-256” or “RSA” to lock your private data, the encrypted files become unreadable without a private decryption key which is only available between your attacker’s hands. They often display a ransom note demanding a ransom payment (usually in Bitcoin or another cryptocurrency). The key to prevent any damage from it is to not run any software from unknown sources.
This type of malware usually targets big companies and not individuals and can cause permanent data loss if not handled properly by their cybersecurity departement or handing the job to a cybersecurity expert. Unfortunately, if the ransomware is developed from scratch by a skillful developer and uses perfect encryption, even top-tier experts can’t break it without the decryption key!
Trojans
Trojans are another dangerous, malicious software that pretend to be safe or useful software but contains hidden malicious code (Usually found in cracked software). This type of malware usually tricks the PC user into willingly running it, and once it inject itself into the system, It is neither easy to detect nor to remove. It’s name came from the famous incident of the “Trojan War” found in the greek mythology, you can read more about it in this Wikipedia article.
Worms
Worms are type of malware that is written specifically to be able to replicate itself and spread to other vulnerable computers without any help from the end user or the malware developer. Unlike viruses, worms can spread through emails and networks and they don’t need to be attached to a specific file or program.
A famous example you might have heard of is the “ILOVEYOU” worm. This particular worm was spread via email with the subject “I LOVE YOU” and was successful because it targeted the weakest point in human nature: curiosity. It ended up infecting millions of computers worldwide.
How Do I Know If My PC Has a Virus?
Some PC viruses are smarter than other ones, they are developed with the intent of not showing any signs a user can detect and thus start taking action, some of them are dangerous as they exploit the vulnerabilities of the core, most critical component of an operating system know as the kernel.
Kernel level attacks are the worst nightmare of any PC user as the attacker can manipulate running applications and services and execute malicious code with elevated privileges. They are called Rootkits, they provide cyberattackers a stealthy, long-term control and are extremely difficult to identify and remove.
Don’t worry, most common PC viruses we disscussed early can certainly be detected by watching your PC behavior or by manually checking some aspects of your machine (For advanced PC users) or by relying on a well-known antivirus or anti-malware software.
Understand Your PC Behavior & Common Signs of Viruses
Let’s start detecting viruses by closely observing virus-related behavior.
Sign 1: Slow PC Performance
A computer virus certainly consumes system resources and that’s the reason why you will start feeling that your PC is not responsive like it was anymore and suddenly becomes sluggish when opening programs or browsing the web.
Sign 2: Frequent OS Crashes, BSODs or Freezes
Some malwares interfer with your system files which leads to random system crashes, blue screens of death (BSODs), or frequent program lags.
Sign 3: Unusual Pop-ups or Ads
Adware usually plays a role in this sign as it is the most common type of malware associated with unexpected pop-up ads that appear in front of your face every time you want to browse the internet.
Sign 4: Unknown Programs Launching Unwillingly
If you are using your computer and a certain program or a CMD window starts popping up randomly, it can be a sign of a malware doing something shaddy in the background, Yikes!
Sign 5: Antivirus or Firewall Disabled
Some malware attempts to disable your security software (whether it’s an antivirus or an anti-malware software) to avoid detection.
Sign 6: High Network Activity
If your internet seems slow recently and you are certain that the problem is not from your ISP, you can start monitoring your network to detect some malware that rely on some outside, external servers to send your important data.
Using Built-in Tools, Antivirus or Anti-Malware Software
PC viruses and malwares can be detected by relying on the built-in tool “Windows Defender” or a famous antivirus like “Kaspersky” or an anti-malware software like “Malwarebytes“.
How To Use Windows Defender
Click on the Start menu and type Windows Security into the search bar and select Windows Security from the search results to open “Windows Defender” built-in tool.
In the Windows Security window, click on “Virus & Threat Protection” from the left sidebar. Under Current Threats, click “Quick Scan”. This will scan common areas for malware. Wait for the quick scan to complete. If threats are found, follow the prompts to remove them.
For a deeper and more thorough check, click “Scan Options” and select “Full Scan”. This will scan your entire system but may take longer depending on the reading and writing speeds of your OS drive.
After the scan is completed, Windows Defender will show you any threats found. If any are detected, it will recommend actions like taking them to quarantine or simply remove them entirely.
How to Use Third-Party Software to Scan for Viruses
Windows Defender provides only basic protection for your operating system. Using third-party antivirus or anti-malware software can improve your system’s security as those tools often come with additional, advanced features and capabilities to detect and remove threats.
They have their virus definitions to detect any type of malware available to a certain point in time. Antivirus or anti-malware software should be updated regularly to keep the virus definitions up to date. Popular options include: Malwarebytes, Bitdefender, Avast and Kaspersky.
First, you have to download the security software by visiting the official website of the antivirus or anti-malware software (e.g., Malwarebytes, Bitdefender, Kaspersky etc.). Choose the Windows version and install it by following the on-screen instructions.
After installation, make sure the virus definitions are up to date. Most antivirus or anti-malware updates definitions automatically, but it’s a good idea to manually check for updates in the settings.
Open the antivirus software and look for the Scan or Start Scan button. You can usually choose between a Quick Scan, Full Scan and a Custom Scan.
A quick scan is a faster scan that looks at the most common areas (folders and directories) for malware. A full scan do a thorough scan of your entire system and it can take several hours depending on how powerful your rig is.
You can also schedule a custom scan which is a type of scan looking in specific folders or drives you specify beforehand for a more targeted analysis. Many antivirus tools allow you to schedule scans. You can set up weekly or daily scans to keep yourself safe and your OS protected.
After the scan is completed, the software you used will display the final results. If malware is detected, it will offer two options: whether to keep it in the quarantine or remove it completely.
Detect Malware By Checking Some Aspects Of Your PC
Open & Check Your Task Manager
Prepare your keyboard and press “Ctrl + Shift + Esc” or you can right-click the taskbar and choose “Task Manager”. You have to click on “More details” if it’s your first time opening it!
Look under the “Processes” tab to see what’s using your CPU, GPU, memory, network and disk drive.
Some suspicious processes can be detected by simply analyzing its name. A process or a software with a random name like xYz1234.exe or DaSdJk.dll can be a red flag!
You can also detect a malware with other signs such as spotting some processes that use too much of your CPU, GPU power or memory without a clear purpose or a running program that you don’t remember installing or any software that keeps restarting automatically after ending it with your task manager. those signs are big red flags.
If you’re unsure about a certain process, Google its name to check if it’s a normal system file or potential malware. You can use websites like ProcessLibrary.com or Should I Block It? for more details.
Open Resource Monitor & Monitor Network Activity
Press Windows + R, type resmon, and hit Enter. Go to the Network tab and look under Processes with Network Activity and Network Activity to see which apps are sending/receiving data.
You have to manually check for suspecious programs using high internet bandwidth without a specific reason, look for unknown or oddly named processes making remote connections with external servers or connecting to multiple foreign IPs, You have to detect any unexpected traffic when your operating system is idle.
Examine Your Browser’s Behavior
Web browsers are often a target for adware, spyware, and other types of malware. If you notice unusual changes in behaviour from your browser, it’s a strong sign that your system may be infected.
Red flags are usually suspicious behaviours and actions like unwanted toolbars or extensions suddenly appearing, unexpected redirections to shady or unrelated websites when you click specific links or open new tabs, unexpected change in your homepage or default search engine without your permission and too much pop-up ads, especially on websites that normally don’t have them.
If you detected some of those red flags, you have to clear your browser’s cache and remove unwanted extensions that are not from trusted sources (e.g., Chrome Store etc.). If problems persist after cleaning up, you should reset your browser to its default settings.
What to Do If You Find a Virus?
Quarantine/Remove Malware & Infected Files ASAP
Most antivirus programs have real-time protection and will automatically quarantine threats or prompt you to remove them. Always choose quarantine first if you’re unsure about a specific file, a quarantine isolates it without deleting it right away. Every antivirus in the market makes mistakes and flag false positive threats.
Update Your Software & Operating System ASAP
Malware often exploits machines with outdated software and systems. Make sure your OS, browser, and programs are all up to date to close security gaps and vulnerabilities.
Change Your Passwords ASAP
If you detect a malware activity, you must change all your passwords especially passwords for email, banking, and social media accounts and be sure to use unique, strong passwords (Above 8 chars or more), and enable two-factor authentication (2FA) wherever possible.
Backup Important Files ASAP
In case of a suspicious virus or malware activity, you must backup your files and data, especially offline backup in other disk drives or cloud-based backups can save your data from loss or ransomware encryption.
Consider Professional Help ASAP
If you’re still seeing signs of infection or feel overwhelmed, contact a cybersecurity expert or a local tech service for a thorough cleanup. The virus might be a stubborn one and in this particular case you have to backup your files, fully format you disk drive and install a new fresh Windows copy.
How To Protect Yourself & Family From Online Threats
In this digital world we live in, it became a skill to be safe online without being leaked or exposed online by some random cyberattacker who will ransom you to keep your life private. Preventing a virus infection is easier than removing one. Follow those guides i wrote to stay safe online:
- Always keep your system and software updated as cybersecurity experts recommend this as the first thing to do as a precaution.
- Always avoid suspicious downloads (Especialy cracked software) or email attachments.
- Always do regular scans on your computer or schedule them at night.
- Always use strong passwords (8 chars and preferably more) and always enable 2FA.
- Always use a reliable and trusted antivirus or anti-malware software
Conclusion
Knowing how to check if your computer has a virus is essential in today’s digital world. In this article we covered a lot of stuff, you learned about different types of malware like keyloggers, ransomware, spyware, and worms, and how to deal with them effectively.
You also learned how to identify suspicious signs, using tools like Task Manager, Windows Defender, and third-party antivirus software to detect malicious software.
We even shared the most important tips on what to do after finding a virus infection and how to prevent them in the future to keep yourself and your family safe and sound!
Always remember this rule of thumb: it’s better to be safe than sorry!
